飞机蒙皮拉伸成形工艺参数优化

拉伸成形是飞机板金的基本成形方法。结合蒙皮拉伸成形常见的缺陷及影响因素,简述了最优化理论结合数值模拟优化工艺参数的必要性。以双曲度蒙皮为例,分析了产生回弹的机理和影响因素。采用正交试验设计建立响应曲面,序列二次规划和混合整数优化相结合的优化算法,以厚度减薄率为约束条件,对成形工艺参数预拉伸率进行优化,并对优化结果进行试验验证。结果表明优化拉形工艺参数后零件变形均匀程度提高,回弹减小了21.87%。

Parameter Optimization in Aircraft Skin Stretch Forming Process

Stretch forming is the basic method for aircraft skin.Defects in sheet metal stretch forming are ana- lyzed.In order to get reasonable parameters,the idea of combing finite element analysis and optimization algo- rithms is adopted,and response surface method is suggested to improve the efficiency of the retrieval.Based on the analysis of the mechanism of springback in double curve skin stretch forming,the reasonable pre-stretch rate is found through the numerical simulation and NPQLP optimization algorithm under the restrictive of max- imal thickness strain.According to the result both numerical simulation and experiment have verified that the strain uniformity is improved and springback is reduced 21.87%.